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NCP Miracle II
161 Richardson-Bass Rd
Kenly, NC 27542
Tel:(919)284-6002 Fax:(919)284-4197
EMail: info1@ncpmiracle2.com
161 Richardson-Bass Rd
Kenly, NC 27542
Tel:(919)284-6002 Fax:(919)284-4197
EMail: info1@ncpmiracle2.com
| Chromium |
Chromium: What is it?
Chromium is a mineral that humans require in trace amounts, although its mechanisms of
action in the body and the amounts needed for optimal health are not well defined. It is
found primarily in two forms: 1) trivalent (chromium 3+), which is biologically active and
found in food, and 2) hexavalent (chromium 6+), a toxic form that results from industrial
pollution. This fact sheet focuses exclusively on trivalent (3+) chromium.
Chromium is known to enhance the action of insulin [1-3], a hormone critical to the
metabolism and storage of carbohydrate, fat, and protein in the body [4]. In 1957, a
compound in brewers' yeast was found to prevent an age-related decline in the ability of
rats to maintain normal levels of sugar (glucose) in their blood [3]. Chromium was identified
as the active ingredient in this so-called "glucose tolerance factor" in 1959 [5].
Chromium also appears to be directly involved in carbohydrate, fat, and protein metabolism
[1-2,6-11], but more research is needed to determine the full range of its roles in the body.
The challenges to meeting this goal include:
• Defining the types of individuals who respond to chromium supplementation;
• Evaluating the chromium content of foods and its bioavailability;
• Determining if a clinically relevant chromium-deficiency state exists in humans due to
inadequate dietary intakes; and
• Developing valid and reliable measures of chromium status [9].
What foods provide chromium?
Chromium is widely distributed in the food supply, but most foods provide only small
amounts (less than 2 micrograms [mcg] per serving). Meat and whole-grain products, as well
as some fruits, vegetables, and spices are relatively good sources [12]. In contrast, foods
high in simple sugars (like sucrose and fructose) are low in chromium [13].
Dietary intakes of chromium cannot be reliably determined because the content of the
mineral in foods is substantially affected by agricultural and manufacturing processes and
perhaps by contamination with chromium when the foods are analyzed [10,12,14]. Therefore,
Table 1, and food-composition databases generally, provide approximate values of
chromium in foods that should only serve as a guide.
Table 1: Selected food sources of chromium [12,15-16]
Food Chromium (mcg)
Broccoli, ½ cup 11
Grape juice, 1 cup 8
English muffin, whole wheat, 1 4
Potatoes, mashed, 1 cup 3
Garlic, dried, 1 teaspoon 3
Basil, dried, 1 tablespoon 2
Beef cubes, 3 ounces 2
Orange juice, 1 cup 2
Turkey breast, 3 ounces 2
Whole wheat bread, 2 slices 2
Red wine, 5 ounces 1-13
Apple, unpeeled, 1 medium 1
Banana, 1 medium 1
Green beans, ½ cup 1
What are recommended intakes of chromium?
Recommended chromium intakes are provided in the Dietary Reference Intakes (DRIs)
developed by the Institute of Medicine of the National Academy of Sciences [14]. Dietary
Reference Intakes is the general term for a set of reference values to plan and assess the
nutrient intakes of healthy people. These values include the Recommended Dietary
Allowance (RDA) and the Adequate Intake (AI). The RDA is the average daily intake that
meets a nutrient requirement of nearly all (97 to 98%) healthy individuals [14]. An AI is
established when there is insufficient research to establish an RDA; it is generally set at a
level that healthy people typically consume.
Adult women in the United States consume about 23 to 29 mcg of chromium per day from
food, which meets their AIs unless they're pregnant or lactating. In contrast, adult men
average 39 to 54 mcg per day, which exceeds their AIs [14].
The average amount of chromium in the breast milk of healthy, well-nourished mothers is
0.24 mcg per quart, so infants exclusively fed breast milk obtain about 0.2 mcg (based on an
estimated consumption of 0.82 quarts per day) [14]. Infant formula provides about 0.5 mcg of
chromium per quart [18]. No studies have compared how well infants absorb and utilize
chromium from human milk and formula [10,14].
What affects chromium levels in the body?
Absorption of chromium from the intestinal tract is low, ranging from less than 0.4% to 2.5%
of the amount consumed [19-25], and the remainder is excreted in the feces [1,23].
Enhancing the mineral's absorption are vitamin C (found in fruits and vegetables and their
juices) and the B vitamin niacin (found in meats, poultry, fish, and grain products) [26].
Absorbed chromium is stored in the liver, spleen, soft tissue, and bone [27].
The body's chromium content may be reduced under several conditions. Diets high in
simple sugars (comprising more than 35% of calories) can increase chromium excretion in
the urine [13]. Infection, acute exercise, pregnancy and lactation, and stressful states (such
as physical trauma) increase chromium losses and can lead to deficiency, especially if
chromium intakes are already low [28-29].
When can a chromium deficiency occur?
In the 1960s, chromium was found to correct glucose intolerance and insulin resistance in
deficient animals, two indicators that the body is failing to properly control blood-sugar
levels and which are precursors of type 2 diabetes [1]. However, reports of actual chromium
deficiency in humans are rare. Three hospitalized patients who were fed intravenously
showed signs of diabetes (including weight loss, neuropathy, and impaired glucose
tolerance) until chromium was added to their feeding solution. The chromium, added at
doses of 150 to 250 mcg/day for up to two weeks, corrected their diabetes symptoms [7,30-
31]. Chromium is now routinely added to intravenous solutions.
Who may need extra chromium?
There are reports of significant age-related decreases in the chromium concentrations of
hair, sweat and blood [32], which might suggest that older people are more vulnerable to
chromium depletion than younger adults [14]. One cannot be sure, however, as chromium
status is difficult to determine [33]. That's because blood, urine, and hair levels do not
necessarily reflect body stores [9,14]. Furthermore, no chromium-specific enzyme or other
biochemical marker has been found to reliably assess a person's chromium status [9,34].
There is considerable interest in the possibility that supplemental chromium may help to
treat impaired glucose tolerance and type 2 diabetes, but the research to date is
inconclusive. No large, randomized, controlled clinical trials testing this hypothesis have
been reported in the United States [14]. Nevertheless, this is an active area of research.
What are the health risks of too much chromium?
Few serious adverse effects have been linked to high intakes of chromium, so the Institute
of Medicine has not established a Tolerable Upper Intake Level (UL) for this mineral [10,14].
A UL is the maximum daily intake of a nutrient that is unlikely to cause adverse health
effects. It is one of the values (together with the RDA and AI) that comprise the Dietary
Reference Intakes (DRIs) for each nutrient.
Chromium is a mineral that humans require in trace amounts, although its mechanisms of
action in the body and the amounts needed for optimal health are not well defined. It is
found primarily in two forms: 1) trivalent (chromium 3+), which is biologically active and
found in food, and 2) hexavalent (chromium 6+), a toxic form that results from industrial
pollution. This fact sheet focuses exclusively on trivalent (3+) chromium.
Chromium is known to enhance the action of insulin [1-3], a hormone critical to the
metabolism and storage of carbohydrate, fat, and protein in the body [4]. In 1957, a
compound in brewers' yeast was found to prevent an age-related decline in the ability of
rats to maintain normal levels of sugar (glucose) in their blood [3]. Chromium was identified
as the active ingredient in this so-called "glucose tolerance factor" in 1959 [5].
Chromium also appears to be directly involved in carbohydrate, fat, and protein metabolism
[1-2,6-11], but more research is needed to determine the full range of its roles in the body.
The challenges to meeting this goal include:
• Defining the types of individuals who respond to chromium supplementation;
• Evaluating the chromium content of foods and its bioavailability;
• Determining if a clinically relevant chromium-deficiency state exists in humans due to
inadequate dietary intakes; and
• Developing valid and reliable measures of chromium status [9].
What foods provide chromium?
Chromium is widely distributed in the food supply, but most foods provide only small
amounts (less than 2 micrograms [mcg] per serving). Meat and whole-grain products, as well
as some fruits, vegetables, and spices are relatively good sources [12]. In contrast, foods
high in simple sugars (like sucrose and fructose) are low in chromium [13].
Dietary intakes of chromium cannot be reliably determined because the content of the
mineral in foods is substantially affected by agricultural and manufacturing processes and
perhaps by contamination with chromium when the foods are analyzed [10,12,14]. Therefore,
Table 1, and food-composition databases generally, provide approximate values of
chromium in foods that should only serve as a guide.
Table 1: Selected food sources of chromium [12,15-16]
Food Chromium (mcg)
Broccoli, ½ cup 11
Grape juice, 1 cup 8
English muffin, whole wheat, 1 4
Potatoes, mashed, 1 cup 3
Garlic, dried, 1 teaspoon 3
Basil, dried, 1 tablespoon 2
Beef cubes, 3 ounces 2
Orange juice, 1 cup 2
Turkey breast, 3 ounces 2
Whole wheat bread, 2 slices 2
Red wine, 5 ounces 1-13
Apple, unpeeled, 1 medium 1
Banana, 1 medium 1
Green beans, ½ cup 1
What are recommended intakes of chromium?
Recommended chromium intakes are provided in the Dietary Reference Intakes (DRIs)
developed by the Institute of Medicine of the National Academy of Sciences [14]. Dietary
Reference Intakes is the general term for a set of reference values to plan and assess the
nutrient intakes of healthy people. These values include the Recommended Dietary
Allowance (RDA) and the Adequate Intake (AI). The RDA is the average daily intake that
meets a nutrient requirement of nearly all (97 to 98%) healthy individuals [14]. An AI is
established when there is insufficient research to establish an RDA; it is generally set at a
level that healthy people typically consume.
Adult women in the United States consume about 23 to 29 mcg of chromium per day from
food, which meets their AIs unless they're pregnant or lactating. In contrast, adult men
average 39 to 54 mcg per day, which exceeds their AIs [14].
The average amount of chromium in the breast milk of healthy, well-nourished mothers is
0.24 mcg per quart, so infants exclusively fed breast milk obtain about 0.2 mcg (based on an
estimated consumption of 0.82 quarts per day) [14]. Infant formula provides about 0.5 mcg of
chromium per quart [18]. No studies have compared how well infants absorb and utilize
chromium from human milk and formula [10,14].
What affects chromium levels in the body?
Absorption of chromium from the intestinal tract is low, ranging from less than 0.4% to 2.5%
of the amount consumed [19-25], and the remainder is excreted in the feces [1,23].
Enhancing the mineral's absorption are vitamin C (found in fruits and vegetables and their
juices) and the B vitamin niacin (found in meats, poultry, fish, and grain products) [26].
Absorbed chromium is stored in the liver, spleen, soft tissue, and bone [27].
The body's chromium content may be reduced under several conditions. Diets high in
simple sugars (comprising more than 35% of calories) can increase chromium excretion in
the urine [13]. Infection, acute exercise, pregnancy and lactation, and stressful states (such
as physical trauma) increase chromium losses and can lead to deficiency, especially if
chromium intakes are already low [28-29].
When can a chromium deficiency occur?
In the 1960s, chromium was found to correct glucose intolerance and insulin resistance in
deficient animals, two indicators that the body is failing to properly control blood-sugar
levels and which are precursors of type 2 diabetes [1]. However, reports of actual chromium
deficiency in humans are rare. Three hospitalized patients who were fed intravenously
showed signs of diabetes (including weight loss, neuropathy, and impaired glucose
tolerance) until chromium was added to their feeding solution. The chromium, added at
doses of 150 to 250 mcg/day for up to two weeks, corrected their diabetes symptoms [7,30-
31]. Chromium is now routinely added to intravenous solutions.
Who may need extra chromium?
There are reports of significant age-related decreases in the chromium concentrations of
hair, sweat and blood [32], which might suggest that older people are more vulnerable to
chromium depletion than younger adults [14]. One cannot be sure, however, as chromium
status is difficult to determine [33]. That's because blood, urine, and hair levels do not
necessarily reflect body stores [9,14]. Furthermore, no chromium-specific enzyme or other
biochemical marker has been found to reliably assess a person's chromium status [9,34].
There is considerable interest in the possibility that supplemental chromium may help to
treat impaired glucose tolerance and type 2 diabetes, but the research to date is
inconclusive. No large, randomized, controlled clinical trials testing this hypothesis have
been reported in the United States [14]. Nevertheless, this is an active area of research.
What are the health risks of too much chromium?
Few serious adverse effects have been linked to high intakes of chromium, so the Institute
of Medicine has not established a Tolerable Upper Intake Level (UL) for this mineral [10,14].
A UL is the maximum daily intake of a nutrient that is unlikely to cause adverse health
effects. It is one of the values (together with the RDA and AI) that comprise the Dietary
Reference Intakes (DRIs) for each nutrient.